Bolt.



PATBNTED JAN. 2l, 1908,.

H. V. WILLE.

' Y BOLT.

APPLICATION FILED MAR.12,1907.

ing, the

UNiTED sTATEs PATENT oEEicE.

HENRY V. WILLE, OF PHILADELPHIA, PENNSYLVANIA.

BOLT.

iippiicaion fue@ March i2. i907. serial No. 361.935.

To all whom it may concern:

Be it known that I, HENRY V. WILLE, a citizen of the United States, anda resident of the city and county of Philadelphia, State ofPennsylvania, have invented certainnew and useful Improvements in Bolts,of which the following is a s ecification.

My invention relates to improvements in bolts and more particularly toimprovements in stay bolts for locomotive boilers and the object of myinvention is to furnish a stay bolt which will not only have sufficientstrength to withstand the longitudinal strains to which such bolts aresubjected but which will also have sufficient elasticity to accommodateitself to the lateral or bending or vibratory strains, which almostinvariably cause such bolts to break.

Stay bolts, in locomotive boilers particularly, give a great deal oftrouble by breakcause being not only the severe strains that areincidental to the particular Vuse of the boiler but to a great extentowing to the unequal expansion between the fire box, to which one of theends of the bolts are secured, and the outer 'shell of the boiler, towhich the other ends of the bolts are secured; the fire box beingsubject to great and varying degrees of heat and the outer shellremaining at practically an even temperature,

the result being that the bolt is constantly subjected to bending .orvibratory strains that presently cause it to break.

In my improved bolt the ends, which are threaded so as to be screwed oneinto the nre box and the other into the outer shell of the boiler, aremade of soft metal so that after being screwed in place they may beheaded or riveted over so asto securely fasten them, and the centralportion, or stem, is made of a iece of metal of high tensile strengthwhich will be sufficiently strong to stand any tensile strains that maybe placed upon it and which will be at the same time sufliciently lelastic to bend without danger of breaking under the strains caused byunequal expansion of the parts to which its ends are secured. In theaccompanying drawings forming art of this specification and in whichsimilar etters of reference indicate similar parts throughout theseveral views:

Figure 1, is a side elevation of a stay bolt of my improvedconstruction; Fig. 2,a section of Fig. 1 on line 2-2; Fig. '3, a sectionsimilar to that shown in Fig. 2, before one of the ends of the bolt isclosed down on the Specification of Letters Patent.

vof a small diameter that a would,

Patented Jan. 21, 1908.

I elevation of a stem, one of the upset ends being threaded on the head;and Fig. 5, an end elevation of the right handed end of Fig. 4.

afa. are the ends ofthe stay bolt which are ymade of soft metalpreferably so that they stem; Fig. 4, a side may be headed over afterhaving them.

screwed into place. If the lire box be of copper I would preferablyconstruct the headtwhich is secured to this part of similar metal or ofone of the alloys of copper suitable for the pur ose.

b is thestem of the bolt which is preferably made of a steel having ahigh tensile strength, and is preferably tempered either before or afterbeing iixed in the soft ends. It is well known that with equal lengthsthe flexibility increases in an inverse ratio to the diameter, the lifeof the boltI therefore, will be greatly increased by having the diameteras small as possible, Provided, however, that the tensile strength .issufficient to meet the requirements of practice, and it is to enable theuse high tensile steel is used and that it is preferably tempered. Thestem being of small diameter will also ,be beneficial to the sheets ofthe firebox as it will interpose a smaller obstruction to the`circulation of the water in the boiler. The ends of the stein b aresecured to the ends a of the bolt in any suitable manner, by welding, byshrinking, by brazing, or by screwing them in, for instance. In Fig. 2,one end of the bolt is shown secured to one end o by welding whiletheother end is shown secured by screw threads.

The bolt may be made of one piece of metal which is susce tible of beingtreated so as to form ends su ciently soft to thread and to hammer overwhile leaving the stem of high tensile strength. The ends a of the boltneed not necessarily be rigidly attached to the stem but a rigidattachment would probably be better as any loose attachment if the boltsbe used as stay bolts for be rendered inoperative by boilers, shortly Iprefer for boiler corrosion or incrustation.

stay bolts to make the stem of a diameter considerably less than theends. Astem of a metal of high tensile strength of three-eighths inchdiameter I have found amply large for this purpose as it has sufficientstrength and great flexibility, permits the use of heads ofcorrespondingly small diameter which is of advantage in that butcomparatively small holes are required in the fire box and boiler I donot desire" be used for many other purposes.

'v parting from the In the drawin s I have. shown both ends ofl thevbolt furnis ed with soft metal ends, it will be understood, however,that but one end of the bolt may be so ended without despirit of myinvention.

-Having thus described my invention, I

claim as new and desireto secure by Letters' Patent:'- A

1. As anew article of manuacture, a bolt havin asoft metal end and astem of metal of hig tensile strength..

v 2. As having a soft metal end and a 'flexible stein of metal of hightensile strength. y 3. A bolt having an exteriorly 'threaded soft metalend and a stem of metalof high tensile strength.

` 4. A bolt having an exteriorly threaded soft metal end and a flexiblestem of metal of high tensile strength.

a new article of manufacture, a bolt*- 5. A bolt having an exteriorlythreaded soft metal end an a flexible stem of temperedor treated steelof high tensile strength. 6. A bolt having an exteriorly threaded softmetal end and a stem of metal of hi h tensile'strength, said stem beingof relative y smaller diameter than said end.

7. A bolt having an end of soft metal and a stem of metal of hightensile strength, said end being secured to said stern.

8. A bolt h flexible stem of metal of high tensile strength the' endof-said stem being enlarged and secured to said end.

9. A bolt lhaving an eXteriorly threaded aving an end of soft metal anda soft metal end containing a threaded cavity or hole and a stem of hightensile strength with threaded end screwed into said cavity or hole.

10. Abolt having an exterorly threaded soft metal end contalning acavity or hole and a stem of hightensile strength, the end of said stembeing enlarged and threaded and screwed into said cavity or hole.

HENRY V. WILLE.

Witnesses:

CHARLES A. RUTTER, F. L. MorsTER.

